Process of producing carbides of sodium and boron



Patented New 6, E23.

tea.

CHARLES E. PARSQNS, 01F ENGLEWOOD, NEW JEB EY.

PRDUESS Gil PBQDUCENG CARBIDES QF SODIUM AND 1803.033.

310 Drawing.

To all whom it may concern:

Be it known that I, Cmnnns E. PAnsoNs, a citizen of the United States, residing at Englewood, in the county of Bergen and State of New Jersey, have invented certain new and useful Improvements in Processes of Producing Carbides of Sodium and Boron; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to a process of simultaneously producing sodium and boron carbides from sodium tetraborate, Na B ,O.,, and carbon, and has for its object to provide a procedure which will be more efficient in action and less costly to carry out than those heretofore proposed.

With these and other objects in view, the invention consists in the novel steps and combinations of steps constituting the process, all as will be more fully hereinafter disclosed and particularly pointed out in the claims.

In carrying out this invention, one may take any suitable quantity of sodium tetraborate, 880 0., or until it is melted, and then raise the molten mass to a temperature above 1000 (3., or better still to about 1200 0., or to a point just safely under its dissociation temperature. To the superheated melt thus had, one now adds an excess of finely divided carbon, such as anthracite coal, coke or charcoal, which is thoroughly admixed with the melted hereto and the temperature raised until substantially all the sodium present sublimes in the form of a carbide leaving boron carbide behind in accordance with the following equation:

The lower boron carbide 13,0 is not directly made by this process so long as a state of fusion exists unless the temperature exceeds 1700 C. It is preferred to make the higher carbide 3 C, by the above disclosed fusion process and to then convert it into the hard dissociation product B C by a separate procedure.

Of course, the operation of producing simultaneously sodium and boron carbides in the manner above stated must be carried out in a closed system; otherwise the sothe furnace chamber by Na B fl heat the same to about.

Application filed April 10, 1923. Serial No. 681,214.

dium carbide Na,C will in contact with the air be burned to sodium carbonate. It is also essential that the sublimed sodium carbide be condensed with the air.

The boron carbide B C can be tapped out of the furnace in the usual manner. It is important that the carbon be not added to been and cooled out of contact It is of course possible to dissociate the boron carbide 13 C without removal from raising the temperature of said carbide to say about 1700 C. after the sodium carbide has been removed by sublimation. By this means, the boron carbide BA], may be broken back to the lower carbide B C.

What is claimed is:

1 The process of making a boron carbide which consists in melting sodium tetraborate, Na B,,O raising the temperature of the molten bath to a point above 1000 C; adding sufiicient carbon to said bath to produce the desired boron carbide; and recovering the product.

2. The process of simultaneously producing sodium carbide and boron carbide from sodium tetraborate, which consists in melting said borate out of contact with the air; raising the temperature to' a point between 1000 C. and the point of dissociation of said borate; addin sufficient carbon to produce the desired so ium and boron carbides; and recovering said carbides.

3. The process of simultaneously making sodium carbide No. 0 and boron carbide B 6 which consists in melting in a closed system sodium tetra-borate Na B,O,; raising the temperature of the molten bath thus produced to a point below that at which said hora-to will decompose; adding sulficient carbon to the bath to produce the desired sodium carbide and boron carbide; and

segregating and recovering said carbide products out of contact with the air.

4. The process of producing a boron carbide which consists in melting sodium tetra- 5 borate; raising the temperature of the melt to a point below that of its dissociation temperature; adding sufficient carbon to produce a higher carbide of boron; still further raising the temperature until said higher carbide dissociates into a lower carbide; and 1 recovering the latter. 7

In testimony whereof I afiizi my signature.

CHARLES E. PARSONS. 

